(though that didn't stop them hiring Samuel Muthafucking Jackson as Nick Fury, so eh)
Just a point of order, but that scenario is actually a bit different from this one.
Nick Fury looking like Samuel L. Jackson is canon, to the Ultimate universe at least. It was an entirely new universe, and they had leeway to change up his looks (helped by Mark Miller being the one to make the change, and as respected as he was at the time, he had some star-power leeway to make changes like that without getting the fans in an uproar). He also said he made the change because the man he felt to be closest in role to Nick Fury in the real world was Colin Powell, so that's why he wanted this new version of Nick Fury to be black. He made him look like Samuel L Jackson because Samuel L Jackson is cool (but didn't bother asking him permission first.)
They modeled the Avengers movies after that run, to a degree.
(I've also seen some varied claims about what happened when Samuel L Jackson found out about it. One I heard but couldn't find a source for was that he said he was fine with it, as long as he got right of first refusal for the role if it went to film, but I couldn't find a source for that with a casual Google search. No matter what, it seems that he was ultimately cool with the decision.)
Back in 2001, Marvel made Nick Fury look like Samuel L. Jackson without asking: His response was perfect
And all that backstory is just sort of ignoring the fact that Nick Fury's race was never particularly key to the character.
edit: This next part is something of a tangent, and not directly in response to your own post.
Though, I will say that it would be... exceedingly difficult to pull off the character as originally written, and it looks like the writers weren't up to the ask.
There is potentially a good story in having someone ending up immersed in a culture foreign to the one where he was born to and raised, returning to their "homeland" and feeling like they doesn't belong in their old world despite the fact that they have responsibilities there. That's a story that people from other nationalities have experience with, when immigrating to the US and emigrating back. There is something to a story involving someone who looks like he should belong in the culture that he's surrounded by but feeling utterly alienated, and people who assume that they should know certain things just because they "look right". (Yes, America is a culture that is varied in races and all, but it is, especially in the upper classes old money cultures that he'd be interacting with, still largely populated by white people.) Having the same thing happen to a white American could be used to broaden empathy towards people from those cultures, maybe understand how certain American traditions can seem offputting or strange.
The example I always liked involved personal space: Americans can seem a bit distant, with the amount of space we like to keep between people that are talking. However, they often get weirded out by people getting close up to their faces, while the foreign people are just trying to (not even consciously, it's not something you usually think of unless something knocks you off balance) make it obvious that they're interested in the conversation and are listening intently. It's something that is about as much an everyday occurrence as it's possible to get, treated vastly differently by different cultures, to the point that people can feel threatened by others trying to be friendly.
There's plenty of room for a story about immigration, holding on to your old culture yet trying to fit in and various attempts to balance that, room for actors with from a variety of ethnicities and cultures (since you'd need people from a similar situation but also dealing with it from a racial/class perspective to show he
still has it relatively good), potential villains (gangs exploiting any tensions and try to be a neighborhood watch yet sink into becoming an extortion racket in a tragic fashion, his old company engaging in exploitative hiring practices, things like that).
Having him be a white actor could have been something more than just tradition, highlighting struggles that most Americans never even have to consider in a format that the people who most needed to learn the lesson would be more likely to be willing to listen to, but it would take a lot of effort and very good writing to pull it off, especially since you kind of need to include the fact that he's a super special martial artists guy. I did like the idea one person proposed in having the title and powers of the Iron Fist essentially be granted to the person they want to use as their emmissary to the outside world, and they figured that a rich white guy with at least a little exposure to that world could probably pursue their interests better then a more talented martial artist who knows little of life outside a dojo. That removes some of the Mighty Whitey implications, and careful writing can take the edge from most of the rest.
Also, the actor wasn't a great fighter and wasn't even given time to train
in a martial arts show, so it was never really going to be good.
(I'd been kind of hopeful that they'd be able to handle all of this tactfully, and make a good show, considering just how much I enjoyed some of the other Netflix Marvel series, but... yeah.)